To release a chip card function, a prior authentication of the user to the chip card may be necessary, as is known per se from the prior art. For this purpose, the user may input authentication data into the chip card via a reader. This is performed for example by inputting a secret character sequence, which is generally referred to as a PIN (personal identification number).
For authentication, the PIN is input by the user via the keypad of a chip card terminal or of a computer, to which a chip card reader is connected, and is then sent to the chip card. This compares the input PIN with the stored PIN and then communicates the result to the terminal or the computer by outputting a corresponding signal.